Aliphatically unsaturated organopolysiloxanes

ABSTRACT

ORGANOPOLYSIOXANES ARE PROVIDED WHEREIN THE ORGANOPOLYSILOXANES HAVE EITHER A TERMINAL AMINO OR ALIPHATICALLY UNSATURATED IMIDO GROUP ATTACHED AT ONE END AND AN ALKENYL GROUP ATTACHED AT THE OTHER END, SAID AMINO OR IMIDO GROUPS BEING ATTACHED TO SILICON THROUGH CARBONSILICON BONDS.

United States Patent once Patented Nov. 6, 1973 ABSTRACT OF THEDISCLOSURE Organopolysiloxanes are provided wherein theorganopolysiloxanes have either a terminal amino or aliphaticallyunsaturated imido group attached at one end and an alkenyl groupattached at the other end, said amino or imido groups being attached tosilicon through carbonsilicon bonds.

This invention relates to novel aliphatically unsaturatedorganopolysiloxanes which have terminal amino or aliphaticallyunsaturated imido radicals attached at one end and an alkenyl groupattached at the other end. Because of the presence of the alkenyl silanebond and the amino or aliphatically unsaturated imido group, it ispossible to incorporate the latter composition into silicon hydridefluids, resins, elastorners, etc., via a platinum catalyzedhydrosilylation reaction.

As an illustration, the novel imidoalkyldisiloxanes can be grafted ontopolyolefins e.g. polyethylene, polypropylene, through the alkenylsilicon linkage and can be homopolymerized through the maleimide portionto obtain polymers with unique properties. Thus, in addition toproviding tough films exhibiting corona resistance, they show goodadhesion to aluminum surfaces, excellent releasing properties andresistance to deformation at high temperatures. In the cured state, thecompositions herein described and claimed can be used as hightemperature insulation for electrical conductors.

In accordance with the present invention, we have discovered a class ofnovel unsaturated organopolysiloxanes having the formula:

Lt .Ll

wherein R is a lower alkyl radical (including cycloalkyl radicals offrom 1 to 6 carbon atoms), phenyl or mixtures thereof;

R is a divalent alkylene radical having 1-6 carbon atoms (includingmethylene, ethylene, propylene, butyl ene, and pentylene);

Y is vinyl, allyl, methallyl or styryl (ortho, meta, or P Z is amino oran aliphatically unsaturated imido group; and

n is an integer equal to at least 1, e.g., from 1 to 1,000 or more. Theterminally functional groups Y and Z are attached directly to siliconatoms by carbon-silicon bonds. Thus, While the Y group is alkenyl incharacter, the Z group may be subdivided into Subclass A having an aminogroup and Subclass B having an aliphatically unsaturated imido group.

The Subclass A having the amino functional group may be expressed by theformula:

wherein R, R, Y, and n are defined hereinabove. These compounds may beprepared by a base catalyzed equilia bration reaction as illustrated bythe specific reaction,

wherein R and R are defined hereinabove. This reaction occurs attemperatures about 25-2-00" 0., and preferably between -120 C.

Subclass B having an aliphatically unsaturated imido group may beexpressed by the formula: f

N R t, o a y C \l wherein R, R, Y, and n are defined hereinabove. Thesymbol R" is a divalent aliphatically unsaturated radical selected fromthe group consisting of radicals having the structure.

and I ti R wherein R, R and R" are defined hereinabove. The reactionoccurs in the presence of acetic anhydride and sodium acetate and/or insolvents such as dimethylformamide and N-methylpyrrolidone, and thelike.

The organopolysiloxanes of the present invention can 'be blended withaliphatically unsaturated organic materials, such as aliphaticallyunsaturated organic monomers, and organic polymers. Blends of theorganopolysiloxanes and aliphatically unsaturated organic material canbe made over wide proportions by weight. Experience has shown that thereshould be employed at least about 15%, by weight, of theorganopolysiloxanes to provide for cured products exhibiting suchvaluable characteristics as corona resistance, solvent resistance,flexibility, etc. Depending upon the proportion of theorganopolysiloxane and the aliphatically unsaturated monomer or polymer,the curable blends can provide for laminates, solventless varnishes,molding compounds, coating compositions, etc. Included by thealiphatically unsaturated monomers that can be employed in combinationwith the organopolysiloxanes are, for example, styrene,diallylphthalate, vinyl chloride, isobutylene, butadiene and isoprene;vinyl esters of organic carboxylic acid, such as vinyl formate, vinylacetate; acrylic esters, such as methyl-, ethyl-, butyl-, etc.; estersof acrylic and methacrylic acids, etc.; and others such asacrylonitrile, divinylbenzene, triallyl citrate, triallyl cyanurate,N-vinyl phthalimide, N-allyl phthalimide, N-allyl phthalimide, N-allyltetrachlorophthalimide, bis (endomethylenetetrahydrophthalimide) ofmethylenedianiline, bismaleimide of methylenedianiline and mixtures withmethylenedianiline and the bismaleimide of methylenedianiline, etc.Among the organic polymers that can be employed in combination with theorganopolysiloxanes of the present invention are, for example,polyvinylchloride, polyethylene, polypropylene, polycarbonates,polysulfones, polystyrene, polyurethanes, polyesters,polyphenyleneoxides, acrylonitrile-butadiene-styrene terpolymers,propylene-ethylene copolymers, etc.

In addition to the aforementioned aliphatically unsaturated monomers andorganic polymers which can be employed with the polysiloxanes, therealso can be employed in proportions, per 100 parts of theorganopolysiloxane, to 200 parts of fillers such as treated clay, groundquartz, fume silica, sand, carbon black, glass fibers, glass beads,carbon fiber, boron fiber, quartz fiber, etc. In addition, otheringredients can be utilized in an amount of from 60% to 90% by weight ofthe total composition, such as solvents including N-methyl pyrrolidone,dimethylacetamide, toluene, methylene chloride, methylacetate,methylethylketone, and plasticizers such as trioctyl trimellitate,diisodecylphthalate, etc.

Our invention is further illustrated by the following examples. Unlessotherwise indicated, all parts are by weight.

EXAMPLE I Preparation of l-(e-aminobutyl)-3-vinyltetramethyldisiloxane Amixture of 0.2 mole (55.2 grams)1,3-bis(6-aminobutyl)tetramethyldisiloxane and 0.2 mole (37.2 grams)1,3-bis(vinyl)tetramethyldisiloxane were heated at 90 C. for 2-3 hoursin the presence of 1.0 gram of potassium hydroxide. The basic catalystwas neutralized with an equivalent amount of a dilute hydrochloric acidsolution, followed by two aqueous washings. Upon distillation undervacuum, a 60% yield of 1-5-aminobutyl)-3-vinyltetramethyldisiloxane(B.P. 84 C./ 0.85 mm. Hg) was obtained. An infrared spectrum of thismaterial showed absorption (microns) for vinyl (3.2, 6.2, 7.1, 9.9,10.4), primary amine (2.9, 3.0), and a broad band at 6.1-6.3.

EXAMPLE II Preparation of 1-(6-tetrahydrophthalimidobutyl)-3-vinyltetramethyldisiloxane A reaction mixture of 0.273 mole (63 grams)1-(6- aminobutyl)-3-vinyltetramethyldisiloxane as prepared in Example Iabove and 0.273 mole (41 grams) tetrahydrophthalic anhydride wascombined in 100 cc. anhydrous dimethylformamide and allowed to stirambient temperatures for two days. The reaction mixture was poured intowater and the organic phase was separated. The organic phase wasextracted with chloroform and the chloroform layer was dried with MgSOand filtered. The dried extract was then distilled over at 187 C./ 2 mm.Hg and there was obtained grams of 1 (B-tetrahydrophthalimidobutyl) 3vinyltetramethyldisiloxane. Th'e product was identified by IR analysisand its purity by vapor phase chromatography was greater than 98%.

EXAMPLE III Preparation of1-(B-maleimidobutyl)-3-vinyltetramethyldisiloxane Following theprocedure of Example II, 0.273 mole (26.8 grams) maleic anhydride wascombined with 0.273 mole (63 grams)1-(B-aminobutyl)-3-vinyltetramethyldisiloxane in 100 ml. ofdimethylformamide. The reaction was exothermic. It was allowed to stirat room temperature for 6 hours and poured into 500 ml. ice water. Thebottom layer (organic) was separated, dried with anhydrous magnesiumsulfate and filtered.

The product was added to 3 molar equivalents of acetic anhydride and 1molar equivalent of sodium acetate and placed on a steam bath for onehour. It was then diluted with two volumes of water, extracted intodiethyl ether, dried and fractionated. The product B.P. 124 C./3 mm. Hgdistilled over in a yield of 45% The resulting product was identified byinfrared analysis as l-(fi-maleimidobutyl)-3-vinyltetramethyldisiloxane.The vaporphase chromatography purity was 97% and nuclear magneticresonance spectrum was consistent with the proposed structure.

EXAMPLE IV A mixture consisting of 20 parts ofl-(tS-maleimidobutyl)-3-vinyltetramethyldisiloxane in 80 parts ofdimethylformamide, and 0.4 part dicumylperoxide was cast on a sheet ofaluminum and heated one hour at C. and then an additional hour at 200 C.

A tough flexible film resulted which showed excellent adhesion to thealuminum substrate and had a cut-through temperature of about 400 C.employing the procedure described in US. Pat. 2,936,296, issued May 10,1960. The film also had excellent release characteristics which wasillustrated by the fact that a transparent adhesive tape did not bond tothe film.

EXAMPLE V Preparation of 1-(5-3,6-endomethylene-A-tetrahydrophthalimidobutyl) -3 -vinyltetramethyldisiloxane Followingthe procedure of Example II, a reaction mixture of molar equivalentquantities of (fi-aminobutyn- 3-vinyltetramethyldisiloxane and 3,6endomethylene-M- tetrahydrophthalic anhydride were combined in thepresence of N,N-dimethylacetamide. An exothermic reaction was noted. Themixture was stirred for 2 hours at room temperature. The solvent wasthen stripped at reduced pressure. To the resulting product was addedthree equivalents of acetic anhydride and one equivalent sodium acetateand the reaction mixture heated on a steam bath for one hour. Thereaction was poured onto ice water and the organic layer extracted twotimes with diethyl ether. The ether layer washed with 10% sodiumcarbonate solution until the washings were slightly basic, dried andstripped leaving behind a product which was identified both by nuclearmagnetic resonance and infrared analysis as 1-(3,6-endomethylene-A-tetrahydrophthalimidobutyl) 3 -vinyltetramethyldisiloxane EXAMPLE VIFollowing the procedure of Example I,l-(v-aminopropyl)-3-allyltetramethyldisiloxane is equilibrated withoctamethylcyclotetrasiloxane using KOH catalyst to obtain 1-('yaminopropyl)-5-allylhexamethyltrisiloxane as one of the components byfractionation.

A mixture consisting of 1-('y-aminopropyl)-5-allylhexamethyltrisiloxaneand a molar equivalent amount of tetrahydrophthalic anhydride arecombined in 100 ml. anhydrous dimethylformamide and allowed to stir atambient temperatures for 2 days. The reaction mixture is poured intowater and the organic phase separated and distilled to give1-('y-phthalimidopropyD-S-allylhexamethyltrisiloxane.

It will be appreciated that the invention is not limited to the specificdetails shown in the examples and illustrations and that variousmodifications may be made within the ordinary skill in the art withoutdeparting from the spirit and scope of the invention.

We claim:

1. An aliphatically unsaturated organopolysiloxane of the formula:

LR it wherein R is a member selected from the group consisting ofmethyl, phenyl and mixtures thereof;

R is a divalent alkylene radical having 1-6 carbon atoms;

Y is a member selected from the group consisting of vinyl and allyl;

Z is an aliphatically unsaturated imido having the formula:

and

and n is an integer of about 1-1000.

2. The organopolysiloxane of claim 1, wherein the compound is 1-(6tetrahydrophthalimidobutyl) 3 vinyltetramethyldisiloxane.

3. The organopolysiloxane of claim 1, wherein the compound is 1-(6maleimidobutyl)-3-viny1tetramethyldisiloxane.

4. The organopolysiloxane of claim 1, wherein the compound is 1-(5 3,6endometh'ylene-Atetrahydrophthalimidobutyl)-3-vinyltetramethylenedisiloxane.

5. The organopolysiloxane of claim 1, wherein the compound is Myphthalimidopropyl)-5-allylhexamethylenetrisiloxane.

References Cited UNITED STATES PATENTS 2,492,554 12/ 1949 Chodroif et a1260326 JOSEPH A. NARCAVAGE, Primary Examiner U.S. Cl. X.R.

